At-risk groups in the UK have been urged to ensure they get a winter flu jab.
An estimated seven million people have already been given the vaccine, but Professor Dame Sally Davies, the Department of Health's chief medical officer, said it is important people with heart or chest problems, liver disease or a neurological illness - as well as the elderly or pregnant - make an appointment at their clinic.
According to the Department of Health, patients with chronic heart disease are 11 times more likely to die than a healthy person if they contract the flu this winter, while it is particularly vital that individuals with a major liver condition are given the medication, as influenza is 48 times more deadly to them than a person with no underlying health problems.
Influenza was first classified in 1933 and constantly mutates to create new strains, meaning it is important patients receive a new vaccination each year, states the Health Protection Agency.
© Adfero Ltd
Private treatment news: 10 November 2011